Sprained ankles are the most frequent type of musculoskeletal injury seen by primary-care providers. More than 23,000 people each day in the United States require medical care for ankle sprains.1 Several muscles control motion at the ankle with each having a tendon connecting the ankle to one or more of the bones of the foot. 1http://www.emedicinehealth.com/ankle sprain/article em.htm
Tendons can be stretched or torn when the joint is subjected to greater than normal stress. Chronic inflammation of a stretched or torn tendon is called tendinitis. Tendons also can be pulled off the bone, called an avulsion injury. Ligaments provide connection between bones. Sprains are injuries to the ligaments.
The ligaments are structures that control excessive movement of the joint. When an ankle sprain occurs, the ligament is overstretched, and is either partially or completely torn. This most commonly happens when the foot is turned inward or inverted. This kind of injury can happen by awkwardly planting the foot when running or stepping up or down on an unstable surface.
A common example is a basketball player who jumps for a rebound and unknowingly comes down on the top of another player's foot. Another basketball example is when a player runs to chase down a loose ball and when he attempts to stop too quickly while running at a high rate of speed, the momentum generated during the chase along with his entire body mass is still propelled forward. Stopping quickly and not having sufficient time to ensure proper placement of the foot or feet can cause severe stress on the athlete's ankle.
Under the aforementioned circumstances, the ankle is most vulnerable to injury (roll and sprain) because the athlete may want to stop, but the body weight and momentum and possibly the weight of another player or two, is disproportionately placed upon the ankle, causing it to turn or roll and therefore, become sprained.
The most common type of ankle sprain occurs when the foot is inverted, falling inward. When this type of ankle sprain happens, the outer or lateral ligaments are stretched too far. About 90% of ankle sprains are inversion injuries.2 The other type of sprained ankle is called an eversion injury, where the foot is twisted outwards. When this occurs, the inner ligament is overstretched. http://orthopedics.about.com/cs/sprainsstranins/a/anklesprain.htm
Ankle sprains also occur during everyday activities. An unnatural twisting motion of the ankle joint can happen when the foot is planted awkwardly, when the ground or landing surface is uneven, or when an unusual amount of force is suddenly applied to the ankle joint. The issue of ankle sprains due to rolling of the foot to the outside edge while engaging in sporting activities is, by far, the most common injury for athletes and amateur sportsman alike.
Prior attempts to solve the problem of an ankle sprain due to rolling of the foot to the outside of the shoe sole, by redesigning the whole shoe support structure, or by immobilizing the side to the side movement of the entire ankle (similar to bracing in hockey skates) have met with only limited success.                U.S. Application No. 20110056097 (Ellis, III) discloses a shoe sole, including at least one insertable midsole orthotic. The insertable midsole orthotic is inserted within the shoe upper, the sides of which hold it in position. The shoe sole includes a concavely rounded side or underneath portion, which may be formed in part by the insertable midsole orthotic. U.S. Application No. 20110056093 (Ellis, III) discloses a shoe, including at least one removable midsole section formed by a midsole portion, wherein the removable midsole section is non-orthotic. The removable midsole section is inserted within the shoe upper, the sides of which hold it in position. The shoe sole includes a concavely rounded side or underneath portion, which may be formed in part by the removable midsole section.        U.S. Pat. No. 7,849,611 (Dean) discloses a built-in or added-on extension situated upon a side of a shoe (at the outer ankle) so as to minimize or prevent injury caused by inversion of a foot or ankle during athletic or other activities. The extension protrudes laterally out from the side of the shoe and generally spherically-shaped insert that may be constructed of a firm but slightly resilient material, such as a firm foam or firm rubber or neoprene.        U.S. Pat. No. 7,918,811 (Lussier; et al.) discloses support devices for joints of the human body. A support device for an ankle includes a main body having a medial portion and a lateral portion disposed about the ankle, and an interior surface; at least one of a medial support member disposed in a cavity in the medial portion of said main body and a lateral support member disposed in a cavity in the lateral portion of said main body; a strap disposed on a proximal portion of said main body.        U.S. Pat. No. 5,109,613 (Van Dyke) discloses a shoe with an integral ankle support preferably for an athletic shoe, having a plurality of adjustable straps and members attached to a shoe upper. The members provide semi-rigid support and are attached medially and laterally to the upper inner surface with a rivet in each member, thereby enabling movement of the members in an anterior and posterior direction about an axis defined by the rivets.        U.S. Pat. No. 4,366,634 (Giese; et al.) discloses an athletic shoe having an injection-molded intermediate portion bonding a fabric upper portion and a rubber outsole portion, for improved fit and comfort and decreased injury-causing fatigue, particularly adapted for use in the playing court-type sports such as basketball. The injection-molded intermediate portion conforms to and partially envelopes the metatarsal area and the heel area of the wearer's foot, and has an intermediate portion which gives lateral support to the instep area of a wearer's foot, such that the shoe moves as a unit together with the wearer's foot.        
No prior attempts to embed a generally rigid brace structure external onto the shoe are known.
The primary object of the anti-roll ankle device of the present invention is to limit or prevent ankle sprains due to ankle rolling or turning, which frequently occurs during court-type sports, both amateur and professional or while jogging especially in real world situations (e.g., parks, sidewalks, wooded areas or streets). What is needed is an athletic shoe or device which will properly address the issue of ankle sprains due to rolling and turning and that provides the athlete with the confidence of full ankle support when it is most needed. What is needed is an athletic shoe or device with an additional support structure (be it to the inside and/or the outside edge of the rear sole of the shoe), or due to landing on an uneven surface, such as landing on another player's foot during a rebound; or by attempting a cross-over dribble and cutting too hard, without proper foot placement. Such unexpected and usually unavoidable injuries have severe consequences not to just the individual athlete, but also to the athlete's team, school, family and fans if said athlete is a key player for the team. If the athlete is an elite professional, an injured athlete can alter the outcome of playoff games, damage the brand or cause loss of revenue (both individually and to team or owner). Even if a player is able to play with an injured or sprained ankle, the player's level of play may be diminished.